Localization

By default, messages, warnings and errors are shown in the current locale.

The language can be changed with Sys.setLanguage:

> Sys.setLanguage("es")
> months[1]
Error in months[1] : objeto de tipo 'closure' no es subconjunto

> help(c("mean", "sd"))
Error en help(c("mean", "sd")): 
  'topic' should be a name, length-one character vector or reserved word

PO & POT Files

Translation via Weblate

The Weblate instance at https://translate.rx.studio provides a user-friendly interface for contributing translations.

The R Project for Statistical Computing

• Most packages have two components for strings in R and C files
• Also translate strings in the Windows and Mac GUIs

Languages tab

• 27 (written) languages in current release of R, including Spanish and Brazilian Portuguese

Translation interface

Enter the translation and “Suggest” (if unsure) or “Save and continue” (if confident).

Sidebar shows alerts and any relevant terms from glossary.

Machine translation

• “Clone to translation” will copy and mark as “needs editing”
• “Accept” will accept suggestion, save and continue

Latin American Contributions

Ongoing work

• Translation of messages in recommended packages:
  • Spanish: 85% translated
  • Brazilian Portuguese: 57% translated
• Updating translations as source messages change
  • R Core Team update 1-2 times a year

Bugs Reports and Feature Requests

Contributors can help in several ways:

Building R as a Barrier to Contribution

• A lot of information to digest
  • Several pages of technical documentation in “R-admin” manual
  • Simplified instructions in R Development Guide, currently for Windows and Ubuntu/Fedora.
• Hard to trouble-shoot issues
• Many pre-requisities to install
• Can interfere with existing R installation

R Dev Container

The R Dev Container provides a development environment that can be run in the browser:

R Dev Container Features

• Launch with GitHub Codespaces (60 hours/month free usage)
• Fixed Linux (Ubuntu) environment, isolated from local system
  • Pre-requisites for building R installed
• Docs with mini tutorials:

R Contribution Workflow

R Contribution Workflow: Build R

Checkout R Sources I

Checkout R Sources II

Get Source of Recommended Packages

Create and Move to Build Directory

Configure the Build I

Configure the Build II

Build R!

Basic check I

Basic check II

Use R-devel in R terminals

R Contribution Workflow: Edit Source

Bugzilla

Bugs and feature requests a tracked on R’s Bugzilla https://bugs.r-project.org

Open Bugs

Bug 7084: A Good First Issue

Bug 7084 is an example of a good first issue:

• There is a simple reproducible example.
• An R Core developer (Martin Maechler) agrees it is a bug.
• There is an outline solution approved by the R Core developer.
• The fix only requires editing R code.

Bug 7084: The Problem

text() recycles coordinate pairs when there are more labels than points

plot(1:7); text(1:2, 2:4, LETTERS[1:4])

Bug 7084: Outline Solution

if (length(labels) > (n <- max(length(x), length(y))) && n >= 1) {
   ## use labels[1:n]  and warn about length(labels) >= .. or "omitting labels[...]"
}
if (length(labels) < n) { 
  ## recycle labels to length `n`  without a warning
}

Start R I

Start R II

Explore text()

Get methods

Finding the Source with the r-svn GitHub Mirror I

Finding the Source with the r-svn GitHub Mirror II

Finding the Source with the r-svn GitHub Mirror III

Navigating the Source Code in the Container

Debugging text.default()

> debug(text.default)
> plot(1:7); text(1:2, 2:4, LETTERS[1:4])

debugging in: text.default(1:2, 2:4, LETTERS[1:4])
debug: {
    if (!missing(y) && (is.character(y) || is.expression(y))) {
        labels <- y
        y <- NULL
    }
    x <- xy.coords(x, y, recycle = TRUE, setLab = FALSE)
    labels <- as.graphicsAnnot(labels)
    if (!is.null(vfont)) 
        vfont <- c(typeface = pmatch(vfont[1L], Hershey$typeface), 
            fontindex = pmatch(vfont[2L], Hershey$fontindex))
    .External.graphics(C_text, x, labels, adj, pos, offset, vfont, 
        cex, col, font, ...)
    invisible()
}
Browse[1]> 

Press Enter to step through the code

debug: if (!missing(y) && (is.character(y) || is.expression(y))) {
    labels <- y
    y <- NULL
}
Browse[1]> 

debug: x <- xy.coords(x, y, recycle = TRUE, setLab = FALSE)
Browse[1]> 

debug: labels <- as.graphicsAnnot(labels)
Browse[1]>

Test code at this point

Browse[1]> x
$x
[1] 1 2 1

$y
[1] 2 3 4

$xlab
NULL

$ylab
NULL

• The labels are already recycled to length n
• Our warnings should be based on x rather than the original arguments

Return to the Source File

Edit the Code

Edit the Documentation

R Contribution Workflow: Rebuild R

Quit R

Rebuild R

Test reprex

R Contribution Workflow: Run check

Basic check

Fail!

Look at test output

Run test code

R Contribution Workflow: Further edits

Further edits

R Contribution Workflow: Rebuild again

R Contribution Workflow: Run check again

Full check

R Contribution Workflow: Create patch

Create patch

Download patch

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